This invention relates generally to gauges and more particularly to an indicating gauge to provide an indication of the level of fluid within a closed container.
Frequently two liquids of different specific gravities will be contained within the same container or tank. This may not always be by design, such as will occur in underground gasoline storage tanks. For instance, water may accumulate within the underground storage tank so that there will be water and gasoline contained in the tank. There is no readily available apparatus to determine the respective levels of the two liquids in a tank. In the past, it has been necessary to open a cover to the underground tank and insert a calibrated pole therein to determine the upper level of the gasoline. This, however, does not provide an indication of the interface level between the water and gasoline. In addition, when opening the cover to make such a level check, fumes from the enclosed tank will escape into the atmosphere which contribute to the ever increasing problem of air pollution. There are numerous float gauges available but none which will provide an accurate dual indication of the upper liquid level and interface level. Prior floats used in these gauges have been subject to joint leakage, etc., such that the accuracy is not reliable.
Accordingly, it is an object of this invention to provide an indicating gauge which will provide a measurement of the surface level of a first liquid and the interface level existing between the first liquid and a second liquid of different specific gravity.
Another object of this invention is to provide an indicating gauge which will permit a liquid level check of an underground tank without opening the tank to atmosphere.
A still further object of this invention is to provide an indicating gauge having accurate system response to changes in respective liquid levels.
And yet another object of this invention is to provide an indicating gauge which is of simple and economical construction and is readily insertable into and removable from existing underground tanks.
And still another object of this invention is to provide an indicating gauge having dual pivoted floats which permit the insertion of the gauge in a narrow inlet yet will permit the floats to rotate in the liquid to provide maximum float energy for the system.
A still further advantageous object of this invention is to provide an indicating gauge which is readily adaptable for either dual level indications or single level indication.
Another object of this invention is to provide an indicating gauge in which the sight glass is wipable from the interior of the tank so as to present a clear viewing area.
A still further object of this invention is to provide an indicating gauge having improved system stability in turbulent conditions and in situations where conditions may cause the riser pipe to be not in a true plumb condition.